Emulsion process for sulfolene and sulfolane products

ABSTRACT

SULFOLENE, A TYPICAL CONJUGATED DIENE CYCLIC SULFONE, IS PREPARED BY EMULSIFYING BUTADIENE IN WATER IN THE ABSENCE OF OXYGEN OR WITH AN ANTIOXIDANT PRESENT, AND THEREAFTER REACTING THE EMULSION WITH SULFUR DIOXIDE UNDER HIGH PRESSURE, FOR A PERIOD SUFFICIENT TO COMPLETE REACTION WITH THE BUTADIENE, WHEREBY YIELDS APPROACHING QUANTITATIVE ARE OBTAINED.

' US. Cl. 260-3321 United States Patent Oflice 3,822,286 EMULSIONPROCESS FOR SULFOLENE AND SULFOLANE PRODUCTS Herbert J. Goldstein,Rockaway, and Hsiao-Jun Li, Morristown, N.J., assignors to Texas-US.Chemical Company, Parsippany, NJ.

No Drawing. Continuation-impart of abandoned application Ser. No.825,385, May 16, 1969. This application Oct. 26, 1971, Ser. No. 192,634

Int. Cl. C07d 63/00, 63/12 1 Claim ABSTRACT OF THE DISCLOSURE Sulfolene,a typical conjugated diene cyclic sulfone, is prepared by emulsifyingbutadiene in water in the absence of oxygen or with an antioxidantpresent, and thereafter reacting the emulsion with sulfur dioxide underhigh pressure, for a period sufiicient to complete reaction with thebutadiene, whereby yields approaching quantitative are obtained.

CROSS-REFERENCE TO RELATED APPLICATION The present application is acontinuation-in-part of application Ser. No. 825,385, filed May 16,1969, now abandoned.

BACKGROUND OF THE INVENTION (1) 'Field of the Invention This inventionrelates to the production of sulfolene. Sulfolene, or butadiene sultone,is a well-known cyclic monosulfone which has considerable value as achemical intermediate (and as a source of pure butadiene by thermaldecomposition). It can be readily hydrogenated to sulfolane, which is avaluable selective solvent for many organic substances, as well as athermally stable inert reaction medium.

(2) Description of the 'Prior Art The conventional method for preparingsulfolene is to mix a large molar excess of liquid butadiene, or theappropriately substituted diene, with liquid sulfur dioxide undernon-aqueous conditions, at pressures between 100 and 500 pounds persquare inch and at a temperature of about 100 C. The reaction timesrequired under these conditions, that is, without some modification ofthe process, can be as high as two days. The bulk of the literature as aconsequence, is largely composed of reports on optimizing this basicprocess.

In addition to the problem of extended reaction times, sulfur dioxideand butadiene in the conventional processes also react to form(insoluble) polymeric butadiene sulfones; generally those conditionswhich increase the reaction rate for the sulfolene reaction alsoincrease the rate for the polymer reaction. 5

Because of these factors, most of the investigative work on sulfolene,and conjugated diene sulfones has been oriented toward improving theefliciency and yield from the sulfolene reaction. This has resulted inthe development of methods involving the use of polymer inhibitors toprevent formation of the polysulfone (U.S. 2,443,270); sodium hydroxidewashing of the butadiene to eliminate peroxides, which favor theformation of polymer (U.S. 2,420,834); and various techniques to achieveimproved results by accurately controlling the temperature of thereaction (U.S. 2,402,891 and 2,395,- 050). Other procedures describe thepreparation of sulfolene in alcohols or other organic substances (U.S.3,077,479). For the most part, however, no significant work has beendirected toward developing a new approach to the actual synthesis ofsulfolene.

3,822,286 Patented July 2, 1974 Accordingly, the fundamental object ofthis invention is to provide a method of preparing sulfolene compoundsin substantially improved yields and in shorter times than can bereached with known methods.

SUMMARY OF THE INVENTION We have discovered that sulfolene can beeliiciently produced by reacting sulfur dioxide with an aqueoussuspension or emulsion of butadiene in approximately equal molar amountsusing a quantity of non-oxygenating water sufiicient at least todissolve all sulfolene formed by the reaction. Conversions in excess of50% and generally higher than 80% are readily obtained by this processin reaction times ranging from one to three hours. Of the reactionproduct obtained, 65% to 100% is sulfolene while the remainder is thesulfone polymer. One of the advantages of the aqueous emulsion reactionwill be immediately evident, when it is noted that sulfolene is verysoluble in hot water, while the polymeric sulfone is very insoluble.Sulfolene dissolves in the aqueous medium virtually as rapidly asformed. The two as a result, can be easily and virtually automaticallyseparated by filtration of the hot aqueous reaction mixture, therebyavoiding any complicated purification procedures or operations. Afurther advantage of the aqueous process is that the excess sulfurdioxide is readily removed as a gas at the end of the reaction, and noneis present in the PREFERRED EMBODIMENTS In the aqueous emulsionpreparation of sulfolene, the most important step is rendering the waternonoxygenating. Water normally contains dissolved oxygen and, as such,it is oxygenating in that it is capable of supplying or imparting activeoxygen to materials in contact with such water. By nonoxygenating waterwe mean water which has been treated to prevent its imparting orreleasing active oxygen either: (1) by deaeration of the water prior tousing it in the system, or (2) as presently preferred, by the additionof an appropriate antioxidant in the water phase of the reaction system.It has been found that the solubility of the antioxidant at the reactionconditions has an important bearing on the yield of sulfolene product.Thus solubility under the proposed reaction conditions is an importantfactor to be considered in the selection of the antioxidant.

If the water is rendered nonoxygenating by deaeration, any conventionaldeaeration means may be used, such as purging the water by providingmeans for intimate contact with a flowing stream or an atmosphere ofnitrogen, inert gas, or steam.

In the absence of deaeration or the incorporation of an antioxidant inthe process water, the product of the aqueous reaction will containabout 15% sulfolene and polysulfone. If the water is renderednonoxygenating by deaeration with nitrogen, the product will containabout 65% sulfolene and 35% polymer.

When the water is rendered nonoxygenating by use of an antioxidant inaccordance with the presently preferred embodiment of this invention,the sulfolene content is increased to the 80% to level with acorresponding drop in the amount of polysulfone. The applicable polymerinhibitors and antioxidants include: Alkyl, aryl, or hydroxyphenol andal-kyl or aryl mercaptan, an inorganic salt of inorganic lower valencesulfur acid, an inorganic salt of inorganic lower valence phosphorousacid, or mixtures thereof. Examples of suitable antioxidants includehydroquinone, sodium dithionite, sodium hypophosphite, sodium sulfide,sodium sulfite, thiophenol, n-octyl mercaptans, n-butyl mercaptan,tert-butylcatechol, and 2,6-ditert-butyl-4-methylphenol. It should benoted that in as much as the sulfolene reaction is conducted underacidic conditions, the seelcted antioxidant must be able to function inan acid medium. Sodium dithionite and sodium sulfide, are acid unstablecompounds which have been found to be exceptions to this requirement,and, as such, are readily applicable for use in the novel process ofthis invention.

The antioxidants are used at levels of 0.1 to 15 parts per 1000 parts ofwater charged into the reactor. The preferred level is 2.5 to 7 partsper 1000 parts of water used.

Inasmuch as the water is to be the continuous phase for the reactionsystem as well as the solvent for the sulfolene product, it is importantto precisely establish the proportions of butadiene and water to be usedprior to forming the emulsion. The reaction which is used in making thisdetermination is CH==CH Under optimum conditions, it is feasible to aimfor a saturated aqueous solution of sulfolene product. This 10 butadieneemulsion to use an emulsifying agent which functions under such acidicconditions. The desired dispersion system may be achieved by the use offrom about 0.05% to 1.0%, based on the weight of water, of anemulsifying agent which may be an anionic, cationic, non- 15 ionic oramphoteric emulsifier. Suitable emulsifiers include sodium laurylsulfate, sulfonated fatt acid derivatives, sulfonates, sulfates,aliphatic phosphate esters, alkanolamides, heterocyclic acids,substituted sarcosinates, salts of sulfosuccinate derivatives of fattyacids, salts of dodecyl 20 sulfate, salts of alkyl aryl sulfonates,salts of monoor 'di-alkyl phosphoric acids, amphoteric salts of fattyacid Z-imidazolinyl compounds, salts of fatty alcoyl sarcosine, andfatty acid alkanolamides. Among those found to be especially effectiveare the following:

Type Trade name Formula Alkylammonium a1kylsulfate Slpex A O CuHn-O- I0NHF t,

:-..: f? 'F III n :s 6 C:Hs J I;

Alkanolammonium alkylsulfate .4 0 CH;

Cn u--0 0 HO-CgH4-N-H t. 3H:

Slpex DEA (I) 'l' 1%! CnHg5-0- 0 HO-CgH4-NCHOH t' I;

Sipex L'1'-6 O H C|,H,;( iSO HOC HI IC,H|=0H g zHAOH SarcosinateSarkosyl 0 0 CH;(CH:)r-CH=CH(CH;)r-iiN-CH:-ii-OH SarooslnataBarkosy1NL-30 CuHu-ii-N-CHz-ii-ONa Alkanolamlde Witamlde No. 272 0 OHCHa-(CH2)7CH=CH(CHI)7-NCH:-Iii-C O Alkanolamlde sulfosuccinste EmcolIII-8300 CH; 0

CH;-(CHz)1-CH=CH(CH,)r-iiCHz-(EHO-ii O Na; 0-CHCH1 Emcol F3250-- 0 CH: 0OH H Alkatnolammonjum alkarylsnlfo- Emco1P10-59 5 TABLE- Continued 6Type Trade name Formula Alkanolmonoglycerlde sulfonate... Sipon M GS100O Sodium lauryl sulfate Duponol WAQE 0111115504 Na ccrszglex organicpolyphosphonie Strodex PK-QO Potassium salt.

----------- sass taster-.1; we

N CH, N 8.2 R=eoconut fatty acid R- N+CH;CH,-O-OHC O 0H R=oetoic acid 0H: C O O- lsoofiigyl llophenyl polyethoxy Triton X-100 CH: CH

The emulsifier is used at levels of 0.5 to parts per 1000 parts of watercharged, and the preferred level is 3 to 6 parts.

Although butadiene is the preferred conjugated diene monomer with regardto the process of this invention, other diene monomers may effectivelyutilized therein. It is thus appropriate to characterize the applicablediene monomers in terms of the following formula:

wherein R R R R R and R are independently selected from the groupconsisting of hydrogen atoms and alkyl, alkenyl, aryl, alkoxy, alkaryl,aralkyl, cycloalkyl, cycoalkenyl and halogen radicals. Among theapplicable conjugated diene monomers are included:

and the like. Needless to say, the use of any of these materials willresult in the preparation of the correspondingly substituted sulfoleneproduct, .and the term sulfolene compound as used herein and in theclaims includes the compound sulfolene and such substituted sulfoleneproducts. For purposes of this disclosure, statements attributed tobutadiene are equally applicable to any of these diene monomers.

EXAMPLE I In the typical practice of this invention 50 to 1700 parts, byweight (1 to 30 moles) of butadiene is dispersed in 1000 parts, byweight, of water containing 0.5 to 10 parts, by weight, of emulsifyingagent, and 0.1 to parts, by weight, of an antioxidant. The dispersaland/or emulsification of the butadiene is carried out under agitation atpressures between 60 and 550 pounds per square inch gauge at about 25 C.The temperature is subsequently adjusted to between 60 C. and 150 0.,following which 60 to 1900 parts (1 to 30 moles) of sulfur dioxide areadded to the emulsion. The broad and preferred ranges of ingredients andoperating conditions for the process are summarized as follows:

The mixture is allowed to react over a period of 1 to 5 hours. At thispoint, to 100% of the butadiene has been converted to sulfolene. Thereaction is cooled gradually to 50 C. to 60 C. and the pressure reducedto 60 to 100 p.s.i.g. The excess sulfur dioxide is either vented off orremoved by treating the reaction mixture with sodium bicarbonate to formsodium sulfite. At this point the reaction mixture is a yellow slurry.The mixture is heated to C. and filtered to remove the polysulfone whichhas formed during the reaction. The pure sulfolene may be recovered bycrystallizing it out of solution by cooling the reaction mixture to roomtemperature or below. The product can further be purified byrecrystallizing from water and/or alcohol a second time. The finalproduct after filtering is vacuum dried and stored for future use, or itis hydrogenated to the saturated compound, sulfolane.

The sulfolene produced by this process has excellent storage stabilityand, as mentioned previously, requires no additional processing toremove residual sulfur dioxide prior to use, as is the case with thecompound prepared by conventional non-aqueous methods.

A variation on' this method consists in recycling the mother liquor in asemi-continuous process. The efficiency of the recycling variation isimproved by the addition of antioxidant to the mother liquor before eachcycle begins. For this purpose, it has been found that between 2 and 7parts of antioxidant provide added protection against the formation ofpolysulfone.

As mentioned previously, the sulfolene produced by this process can bereadily hydrogenated to the saturated form of the molecule. This can beaccomplished with a conventional technique using Raney nickel,pelletized supported nickel, palladium oxide, platinum oxide, etc. ascatalyst. Generally between 5% to 20% of the catalyst based on theweight of sulfolene will be sufiicient to produce satisfactory results.The hydrogenation reaction can be conducted at temperatures between 40C. and 50 C. and at pressures of about 60 p.s.i.g. or at elevated tem- 7peratures between 50 C. and 100 C. at much higher pressures of about 600p.s.i.g. Between 1 to 7 hours and usually about 4 hours, are required toobtain conversions at the 85% level.

The following examples will afford a better understandutes. Liquidsulfur dioxide was then added to the reactor with stirring. Thereactants were heated rapidly to 90 C. and then maintained above 90 C.and below 130 C., with stirring, for about 3 hours. The temperatureinside the reactor was measured by a Weston dial thermometer,

. mg of the invention to those skilled in the art. and aniron-constantan thermocouple. The temperature of the heating jacket wasmeasured with an iron-con- EXAMPLE H stantan thermocouple.

This example demonstrates the practice of this mven- The pressure insidethe reactor increased from 6 tion utilizing a variety of antioxidantsand emulsifying p.s.i.g. to a maximum of nearly 400 p.s.i.g., and thenagents in aqueous and aqueous emulsion yst ms- The dropped rapidly. Uponconclusion of the reaction, as indieXPel'imefltS in this sequence ofeXamPIeS also eXhihIt the cated by the stable lower pressure of about80-100 p.s.i.g., use of a number of different temperature and pressureth reactor was l d gradually t about 50 t 60 C., conditions. Their totaleffect can be udged from the da during which time the pressure decreasedfurther to about reported In Tables A and 13 bel 60 to 80 p.s.i.g. Thereactor was vented to eliminate ex- Specrfically the data in Table IAillustrates the improvecess lf di id nd the ont nt removed. ment insulfolene yield and total conversion in a water Th ti i t was ayellowish slurry. Thi was System accompanied y Water deaeration /O e ofheated to 85 C. and stirred until the yellowish color appropriateantioxidants. The data in Table IB illustrates changed gradually twhite, The whit slurry wa then comparable results lhl'eugh the use ofemulslell Systems filtered. The residue was digested with hot water andwith appropriate emulsifiers and ant1oX1dan s. filtered, after which thefiltrates were combined. On

The basic Procedure for eonduetlng these eXPeflmentS cooling, whitecrystals separated. Additional product was involved dissolving theantioxidant and 2.1 grams of emulobtained by concentrating the motherliquors. The comsifying agent in deaerated redistilled water by heatingbined product was dried by suction and finally dried over and thencharging the soap solution into a 2000 milliliter 5 calcium chlorideunder vacuum.

Parr Series 4500 stirred reactor. Liquid butadiene, puri- The waterinsoluble product, i.e., the butadiene polyfied by passing it through analumina column, was charged sulfone, was dried in air and then overcalcium chloride into the reactor and the contents were stirred for 15mlnunder vacuum.

TABLE IA [Reaction of butadiene and suliur dioxide in water system]Antioxidants Butadiene S0, butadiene Peak Peak Percent Percent (gm.-(gm.- m.-mols) ressure temp Time Percent B-suiiopolymols) mole) (ratio)p.s.i.g.) 0.) (hrs conv. lene sulfone 3. 7e 3. 95 1. 05 490 127 3% 76 991 3. 71 3. 75 1. 01 400 145 4 78 15 85 3. 75 3. 79 1. 01 420 120 3%, 8305 3. 71 3. 75 1. 01 450 121 31-3 86 99 1 3. 71 4. 05 1. 09 510 128 4 8789 11 3. 71 3. 75 1. 01 500 128 4 85 94 6 5. 55 5. 60 1. 01 500 129 4 8897 3 5. 55 5. 1. 01 400 125 3% 90 98 2 5. 5. 80 1. 01 570 132 3% 80 99 15. 55 5. 1. 01 530 133 4% 89 99 1 1 Hydroquinone. 3 Freshly deaerated.

TABLE 13 [Reaction of butadiene and sulfur dioxide in emulsion system]Antioxidants Buta- S01:

diene BO, butadiene Peak Peak Percent Percent water Amount (gm.- .-mols)pressure temp. Time Percent; a-suliopoly- Run (grams) Emulsifler Type(gms) mois) mole) ratio) p.s.i.g.) 0.) (hrs) oonv. lene sullone 1 900Emcol P1059.- Ionol l a 3.30 8. 22 1. 200 44 18 100 32 3 2 1 (in HQ? 31.98 3.28 1.53 200 44 13 80 3 450 --.--do ThKioglbenolpllls 7 2.113.51 1. 30 100 31 19 39 18 82 s. 4 45 do 3 1.85 3.83 2.00 300 100 13.498 2 3 1.85 3. 57 1.98 100 45 10 79 97 3 3 1.94 4.15 2.14 330 100 1 8474 23 3 1.85 3.13 1.59 335 120 3% 85 99 1 0. 8 450 Emeol P1059... TBC 33 1.87 1.87 1.01 360 112 3% ;..:;I:

Percent yield Antioxidant Buta- 80;: Beat:- ofdiene S0, butadiene PeakPeak tion Percent w t Amount (grm- (gm-mole; ressure temp time eonver-8-sul- Poly- (grams) Emulsifier Type (gms.) mols) mole) (ratio p.s.i.g.)0.) (hrs.) sion iolene sulione 450 Emcol P1059 II'CBHHSH 3 2.11 3.011.43 300 97 1% 79 5 450 do n-C HnSH 3 2.23 3.95 1.77 380 110 1 82 95 5450 do 82 3 3 2.11 3.33 1.58 350 103 1%, 42 53 450 do NaiS9H,o 3 2.113.23 1.54 370 1 94 99 1 450 do Nels, i 3 1.95 3.45 1. 77 380 120 1% 9287 13 450 .-do a i olHio 3 1.95 3.58 1.83 380 123 2 88 97 3 450Witeamide No. 272-.-- Nazsflol 1 1. 87 1.83 0.98 370 120 4 73 99 1 450do 1 2.00 1.88 0.94 400 130 2 ,4 81 93 4 450 1 1.85 1.89 1.02 390 117 3%78 98 2 45d 3 2.05 2.40 1.17 310 120 2% 81 99 1 300 2 1.67 1.91 1.14 340100 1 30 80 20 450 3 1. 95 1. 95 1.00 355 120 3% 75 99 1 300 do Ho. 31.85 1.72 0.93 320 100 25/2 09 91 9 450 Emcol 1 32-50 HG 3 1. 80 2.031.11 300 105 1 55 82 18 450 (in 3 1.97 1.93 1.00 330 111 215 32 92 8 450Emcol K8399 HQ. 3 1. 95 1.83 0.94 330 112 3 79 91 9 450 SipexA H 3 1.802.08 1.12 340 110 3% 37 90 10 450 Sipex DEA Ht; 3 1.93 2.03 1.05 380 122214 66 8e 14. 450 Sipex L'rs Ho. 3 1.85 1.87 1.01 390 2% 70 89 11 450SiponMGSlOO di- H 3 2.94 1.88 0.92 320 110 2 73 90 10 ethylamine.

See footnotes at end of table.

EMBED-Continued Percent ield Antioxidant Bute- S01: Reacoidiene 80:butadiene Peak Peak tion Percent Water Amount (gm- (grm- -mols) pressuretemp. time conver- 3-sul- Poly- (grams) Emulsifler Type (gms) mols)mols) (ratio) (p.s.i.g.) 0.) (hrs.) sion iolene suliona 4.50Laurylsnifate di- HQ 3 1.85 1.84 1.00 340 113 3 51 86 14nfihylethanolne. Laur lsulfate HQ... 3 1.76 1.88 1.05 390 122 2 70 90 10Triton X-100 HG. 3 1.91 1.85 0.97 400 110 3 66 86 14 Witcamide No. 272.HQ 3 l. 91 1. 87 0. 98 390 115 3% 80 98 2 do HQ 3 2. 08 1. 88 0. 91 310128 3% 92 99 1 Barkosyl O Hi; I 3 1.85 1- 88 0.95 380 115 1% 76 83 17Sarkosyl N L-30 HG 3 2. 04 1. 94 0.92 360 111 2 68 97 3 900-. SF Flake 5HG 3.76 3.70 1.00 520 130 3 69 99 1 900.- Duponol WA E HQ- 0 3.71 3.971.07 520 130 3% 88 93 7 900.- Miranol Jem. conc.)- HQ. 6 3.81 3.77 0.99500 122 3% 72 99 1 900.. Miguel $12MSF Ht; 0 3.71 3. 75 1.01 510 130 3%84 99 1 one. 900..;-.-.. Strodex PK-90 HQ.-- 6 3.71 3.75 1.01 510 125 3%80 95 l 2,6 di-tert-butyl 4-methyl phenol. 3 Hydroquinone. I Tertiarybutyl catechol.

4 Actual temperature rather than peak temperature: Sodium salt ofpartially hydrogenated tallow fatty acid.-

EXAMPLE III This Example demonstrates the use of recycled mother liquorin the process of this invention.

The reactions shown in Table II were conducted in the same manner as inExample II. In Experiment '1, the reactants were prepared and chargedinto the reactor as in Example II In Experiment 1A through IF, themother liquor resulting from Experiment 1 was used as the reactionmedium without additional antioxidant being added. An additional 2 gramsof hydroquinone were added to the mother liquor of Experiment 2 which,in turn, was used in Experiments 2A through 2E. For Experiments 2Fthrough 21, the mother liquor resulting from Experiment 2B was usedwithout the use of additional antioxidant. In each of the predominantExperiments (Experiments '1 and 2), the reaction charge contained 450grams of water and 2.1 grams of Emulsifier Emcol P1059.

oxide/water. The sulfolene is known to dissolve in both the water anddispersed phase. Thus it must partition itself between these two. So,also must any antioxidant added to the water phase. The degree to whichthe antioxidants dissolve in the two phases is dependent on theirindependent solubilities in each phase. Thus, in Example II, Table IA,hydroquinone, sodium dithionite ('Na S OL and sodium hypophosphite (NaH-PO -H O) are all very soluble in hot water. The efiect of watersolubility of the antioxidant coupled with-the elfect of waterdeaeration (run 3, Table IA) show that in this system the antioxidant inthe water phase governs the course of the reaction.

' The effect of antioxidant solubility in the water phase usingemulsifiers is clearly shown by comparing the data of Table I8 of thespecification. Thus, Ionol (2,6-ditertiary butyl-4-methylphenol) whichis a water insoluble stabilizor for styrene and other polymerizable oroxidizable hy- TABLE II [Reaction of butadiene and sulfur dioxide inemulsion system] Hydfo- SOmbuta- Peak Peak Reaction Percent yield 01-quinone Butadiene Oz diene pressure temp. time Percent Experiment (gms)(gm-mole) (gm-mole) (ratio) (p.s.i.g) 0.) (hrs.) conversion 3-suliolenePolysulfone 3. 71 3. 75 1. 01 320 127 3% 71 99 1 3. 71 3. 75 1. 01 450140 3% 64 B0 20 3. 71 3. 75 1. 01 380 120 4 94 B4 16 3. 71 3. 75 1. 01380 120 4 76 90 10 3. 71 3. 75 l. 01 400 132 4 86 78 22 3. 71 8. 75 1.01 460 130 4% 81 76 24 3. 71 3. 75 1. 01 400 127 4 83 75 25 4. 10 '3. 0.83 400 123 3 99 1 3. 71 3. 1. 01 420 130 3% 89 11 3. 71 3. 78 1. 02 410127 3 92 87 13 3. 71 3. 75 1. 01 400 3% 87 99 1 3. 71 3. 75 1. 01 495 384 93 7 3. 71 3. 78 1. 02 460 133 3% B9 96 4 3. 71 4. 10 1. 10 500 132 391 93 7 3. 71 3. 86 1. 04 460 130 310/60 90 99 1 3. 71 3. 82 1. 03 4801310 300/60 92 92 8 3. 71 4. 05 1. 09 420 120 350/60 86 99 1 3. 71 3.75 1. 01 480 130 430/ 60 91 99 1 1 Grams of hydroquinone in addition toamount present in mother liquor.

It is known that diolefinic conjugated hydrocarbons, like butadiene, arerelatively insoluble in water. Likewise, as set forth in Kirk-OthmerEncyclopedia Chemical Technology, Vol. 13, pp. 417-420, The InterscienceEncyclopedia, Inc., New York (1954) states:

Sulfur dioxide dissolves in water to form the weak acid, sulfurous acid,H 80 At a partial pressure for sulfur dioxide 'gas of 1 atm., solutionscontaining 18.5% S0 by weight are formed at 0 C. and 5.1% strength at 40C. Under practical conditions where solutions are formed most often .at'1 atm. total pressure with air or other diluent gases present,concentrations of from only V3 to of these values are obtained.

It is thus seen that both reactants in the instant aqueous dispersionprocess are relatively insoluble in the water medium, or at best, onlypartially soluble.

It is believed that the reaction between butadiene and EXAMPLE IV ThisExample demonstrates the catalytic hydrogenation of 3-sulfolene preparedaccording to the process of this invention.

The hydrogenation of 3-sulfolene was conducted in aqueous solution usingpowdered or pelleted nickel cata- SO, occurs in a dispersed phase ofbutadiene/sulfur di- 75 lyst and was carried out at 60 p.s.i.g. at atemperature of 40 to 50 C. A 2000 ml. Parr Series 4500 stirred the firstthree experiments, high yields of sulfolene prod- Reactor and a 450 ml.Parr Series 3910 shaker type uct were obtained. hydrogenation apparatuswere employed. EXAMPLE VI A Parr Series 4500 stirred Reactor was usedfor hydrogenations at 100 p.s.i.g. or higher. {Comparable results wereobtained with pentadiene-LS The catalyst, 3-sulfolene, water and otheringredients (p p under the Same reaction itions as deshown in Table IIIwere added to the reactor which was scribed n Example V With theexception that the Product then closed and evacuated with a water pump.After was q I purging h reactants three times i h h d h Summarizing, lt1s thus seen that this invention provldes tion mixture was stirred orshaken under a hydrogen a novel and eflicient P P p 0f SulfO- pressureof 60 p.s.i.g. or higher and at 40 C. to 50 C. for lene and sulfolaneproducts. varlatlons may be made in h i d of i shown i bl 111proportions, procedures and materials without departing After absorptionof the hydrogen ceased, the reactor f h Scope of thlS lllventlon asdefined in the followwas opened and the catalyst filtered off. Water wasreg dalmmoved by distillation at atmospheric pressure or under a W im!vacuum. The residue was treated with methyl alcohol to A method the p p0f Sulfolene Comrecover unreduced 3-sulfolene. The alcohol solution wasPoundS hy flifect Fohdmsattoh 0f cohl'uhgated d es w th flash distilledto remove the methyl alcohol and the resisulfur dwxldp which wrpprlsesthe steps due was then distilled at 136 C.-138 c. at a pressure ofselectme a quantity of water for the reaction, and 3 to 4 mm. in orderto obtain the pure sulfolane. purging said water with a member selectedfrom the Results of these procedures are presented in Table IH. groupconsisting of nitrogen, inert gas and steam TABLE III [Catalytichydrogenation of 3-sulfo1ene in water] Catalyst Percent AdditivesReaction Initial H2 H2 yield 3-suitolene Wt. temp. rcssure absorbed Timepur Water (grams) (gm.-mols) percent Type Grams C.) p.s.i.g.) (gm.-mo1s)(hrs.) sulfolane 0. 5 4 Emcol P1059 2 Ambient 530 0. 64 1M 0. 85 10 -600. 01 4 85 0 125 40-50 60 0.13 3 60 0 125 40-50 60 0.13 0% 0. 125 40-5060 0. 18 5 70 0 125 40-50 60 0.15 5 83 0 125 40-50 60 0.15 6 87 0. 12540-50 51 0. 15 3% 0. 40-50 61 0. 157 16 80 0. 125 40-50 0. 157 16 80 3.81 50-60 300 3. 7 7}, 32. 5 3. 81 50-60 300 3. 7 8% 80. 5

EXAMPLE V to render said quantity of water non-oxygenatmg;

(2) dispersing in said water a conjugated diene mono- Thls exampledemonstrates the use of 2-methyl-1,3- met corresponding to the formulabutadiene (isoprene) in the process of this invention. 45

The reactions shown in Table IV were conducted in the n, same manner asin Example H with the exception that 2- methyl-1,3-butadiene (isoprene)was substituted for the butadiene. R1 I 34 RI TABLE IV [Reaction of2-methyl-1,3-butadiene (isoprene) and sulfur dioxide in emulsion system]Percent yield ot- Emcol Hydroqui- 80 P1059 none isoprene Peak PeakReaction Percent 3-methyl-3- Water emulsifier antioxidant Isoprene S09(mole pressure temp. time conversion sulfolene Polysulione (gms.) (grns)(gins) (moles) (moles) ratio) (p.s.i.g.) 0.) (hrs.)

1.47 1.56 1 06 220 12s 3% 75 99 1 1. 47 1.56 1 06 220 3% 79 99 1.47 1.561 06 200 125 67 84 161 1. 47 1.56 1 66 165 12a 3% s5 18 e5 1. 47 1.56 106 195 130 3% s2 15 a2 1 Freshly deaerated distilled water.

In addition to further illustrating the effectiveness of wherein R R R RR and R are independentthe process of this invention, the data presentedin the ly selected from the group consisting of hydrogen above tableindicates the necessity for utilizing non-oxyatoms and alkyl, alkenyl,aryl, alkoxy, alkaryl, arakgenating water such as deaerated water and/orwater hav- 7 yl, cycloalkyl, cycoalkenyl and halogen radicals; in ing anantioxidant therein in order to obtain high yields an amount from 5% toof the weight of the of sulfolene product in contrast to polysulfone.Thus a water medium; comparison between the first three experiments andthe (3) adding to said diene in water dispersion from 6%- last twoexperiments in Table IV clearly indicates that of sulfur dioxide, asbased on the weight of where the oxygen eflect on the system wasinhibited, i.e., 75 water, at a pressure of 60-550 pounds per squareinch 13 and a temperature of from 60 C.-150 C., for 1 to 5 hours toreact said sulfur dioxide with said diene dispersion and to producethereby a reaction mixture comprising a water slurry containing asolution of a sulfolene compound and a polymeric sulfone; (4) droppingthe pressure to ambient levels; and (5) filtering said hot reactionmixture to remove said polymeric polysulfone from said solutioncontaining the sulfolene compound.

References Cited UNITED STATES PATENTS 14 2,578,565 12/1951 Mahan et a1260-3324 FOREIGN PATENTS 236,386 7/1911 Germany 260332.1 506,839 9/ 1930Germany 260332.1

OTHER REFERENCES McCutcheon, Detergents & Emulsifiers (Allured Pub. Co.,Ridgewood, NJ., 1970), pp. 87, 94, 95, 149, 194, 202, 243, 255.

Chemical Rubber Handbook (Chem. Rubber Pub. Co., Cleveland, Ohio, 1962),pp. 876-879, 1030, 1031, 1038,

1,196,259 8/1916 Matthews et al. 260-3321 2,395,050 2/1946 Hooker et al260-327 1 HENRY LES, Examm" 2,443,270 6/1948 Robey et al. 260-329 5 C-M- JAISLE, Assistant Examiner I UNITED STATES PATEIfiT OFFICECERTIFICATE OF CORRECTION Patent No. 3,822,286 Dated July 2, 1974-Inventor(s) .Herbert J. Goldstein Hsiao-Jun Li It: is certified thaterrorvappears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Column 3, line3, "seelcted" should be selected Column 4, line 7,"buadiene" should be butadiene Column line 7, er "effectively" insert bTable IB, Run "8, Butadiene (gm-mols) column, "1.87"

should be 1.85

Table IV, P ei'c ent yield of Polysulfone column, the numerals readingdown "l, 5, 161, 85, 82" should be l, 1, 16, 82,

Column 12, line 16, "conjungated" should be conjugated Signed and sealedthis 5th day of November 1974.

(SEAL) Attest: McCOY M. GIBSON JR. (3. MARSHALL DANN Attesting OfficerCommissioner of Patents FORM PO-105O (IO-69) USCOMM DC BONGJJGQ u.s.GOVERNMENT PRINTING OFFICE: I969 o-ass-au

